Obfuscated-AHA [Trj]; reste-t-il des virus?

Bonjour,

j'ai été récemment infecté par un trojan, signalé par Avast comme Win32:Obfuscated-AHA [Trj]. Je l'ai supprimé et tout a l'air de s'être bien passé, mais je souhaiterais en être certain. Je joins à ce message un rapport de HijackThis comme tout le monde semble l'avoir fait. Je précise que je n'ai pas de logiciel P2P.
Logfile of HijackThis v1.99.1
Scan saved at 18:54:53, on 07/07/2007
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16473)

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\winlogon.exe
C:\WINDOWS\system32\services.exe
C:\WINDOWS\system32\lsass.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Intel\Wireless\Bin\S24EvMon.exe
C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
C:\Program Files\Alwil Software\Avast4\ashServ.exe
C:\WINDOWS\EXPLORER.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\system32\DRIVERS\CDANTSRV.EXE
C:\Program Files\Intel\Wireless\Bin\EvtEng.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\rundll32.exe
C:\Program Files\Java\j2re1.4.2_03\bin\jusched.exe
C:\Program Files\Fichiers communs\Microsoft Shared\VS7DEBUG\MDM.EXE
C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
C:\Program Files\Dell\QuickSet\NICCONFIGSVC.exe
C:\WINDOWS\System32\DLA\DLACTRLW.EXE
C:\Program Files\Fichiers communs\Microsoft Shared\Works Shared\WkUFind.exe
C:\Program Files\HP\HP Software Update\HPWuSchd2.exe
C:\Program Files\Broadcom\BACS\BacsTray.exe
C:\Program Files\Dell\Media Experience\DMXLauncher.exe
C:\Program Files\Dell\QuickSet\quickset.exe
C:\WINDOWS\system32\nvsvc32.exe
C:\Program Files\Intel\Wireless\Bin\RegSrvc.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\RUNDLL32.EXE
C:\Program Files\Intel\Wireless\Bin\WLKeeper.exe
C:\WINDOWS\stsystra.exe
C:\Program Files\Intel\Wireless\bin\ZCfgSvc.exe
C:\Program Files\Intel\Wireless\Bin\ifrmewrk.exe
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Digital Line Detect\DLG.exe
C:\Program Files\HP\Digital Imaging\bin\hpqtra08.exe
C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
C:\Program Files\HP\Digital Imaging\bin\hpqimzone.exe
C:\Program Files\HP\Digital Imaging\bin\hpqSTE08.exe
C:\Program Files\Intel\Wireless\Bin\Dot1XCfg.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Documents and Settings\Pierre\Bureau\hijackthis_hijackthis_1.99.1_anglais_17891.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = https://www.dell.com/fr-fr
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://mysearch.myway.com/jsp/dellsidebar.jsp?p=DR
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.google.fr/?gws_rd=ssl
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = https://www.msn.com/fr-fr/?ocid=iehp
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = https://www.bing.com/?toHttps=1&redig=5FC791212101479BAFBE1A679848B1AF
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = https://www.bing.com/?toHttps=1&redig=5FC791212101479BAFBE1A679848B1AF
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.msn.com/fr-fr/?ocid=iehp
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
R3 - URLSearchHook: (no name) - {4D25F926-B9FE-4682-BF72-8AB8210D6D75} - (no file)
F2 - REG:system.ini: Shell=C:\WINDOWS\EXPLORER.EXE
O2 - BHO: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.dll
O2 - BHO: (no name) - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: DriveLetterAccess - {5CA3D70E-1895-11CF-8E15-001234567890} - C:\WINDOWS\System32\DLA\DLASHX_W.DLL
O4 - HKLM\..\Run: [NVHotkey] rundll32.exe nvHotkey.dll,Start
O4 - HKLM\..\Run: [SunJavaUpdateSched] C:\Program Files\Java\j2re1.4.2_03\bin\jusched.exe
O4 - HKLM\..\Run: [SynTPEnh] C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
O4 - HKLM\..\Run: [ISUSPM Startup] "C:\Program Files\Fichiers communs\InstallShield\UpdateService\ISUSPM.exe" -startup
O4 - HKLM\..\Run: [ISUSScheduler] "C:\Program Files\Fichiers communs\InstallShield\UpdateService\issch.exe" -start
O4 - HKLM\..\Run: [DLA] C:\WINDOWS\System32\DLA\DLACTRLW.EXE
O4 - HKLM\..\Run: [Microsoft Works Update Detection] C:\Program Files\Fichiers communs\Microsoft Shared\Works Shared\WkUFind.exe
O4 - HKLM\..\Run: [HP Software Update] C:\Program Files\HP\HP Software Update\HPWuSchd2.exe
O4 - HKLM\..\Run: [bacstray] C:\Program Files\Broadcom\BACS\BacsTray.exe
O4 - HKLM\..\Run: [DMXLauncher] C:\Program Files\Dell\Media Experience\DMXLauncher.exe
O4 - HKLM\..\Run: [Dell QuickSet] C:\Program Files\Dell\QuickSet\quickset.exe
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [nwiz] nwiz.exe /install
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\WINDOWS\system32\NvMcTray.dll,NvTaskbarInit
O4 - HKLM\..\Run: [SigmatelSysTrayApp] stsystra.exe
O4 - HKLM\..\Run: [IntelZeroConfig] "C:\Program Files\Intel\Wireless\bin\ZCfgSvc.exe"
O4 - HKLM\..\Run: [IntelWireless] "C:\Program Files\Intel\Wireless\Bin\ifrmewrk.exe" /tf Intel PROSet/Wireless
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - Global Startup: Digital Line Detect.lnk = ?
O4 - Global Startup: Démarrage rapide de HP Photosmart Premier.lnk = C:\Program Files\HP\Digital Imaging\bin\hpqthb08.exe
O4 - Global Startup: HP Digital Imaging Monitor.lnk = C:\Program Files\HP\Digital Imaging\bin\hpqtra08.exe
O4 - Global Startup: Lancement rapide d'Adobe Reader.lnk = C:\Program Files\Adobe\Acrobat 7.0\Reader\reader_sl.exe
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~4\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\j2re1.4.2_03\bin\npjpi142_03.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\j2re1.4.2_03\bin\npjpi142_03.dll
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~4\OFFICE11\REFIEBAR.DLL
O9 - Extra button: (no name) - {CD67F990-D8E9-11d2-98FE-00C0F0318AFE} - (no file)
O11 - Options group: [INTERNATIONAL] International*
O16 - DPF: {01A88BB1-1174-41EC-ACCB-963509EAE56B} (SysProWmi Class) - http://support.euro.dell.com/systemprofiler/SysPro.CAB
O16 - DPF: {0EB0E74A-2A76-4AB3-A7FB-9BD8C29F7F75} (CKAVWebScan Object) - https://www.kaspersky.fr/?domain=webscanner.kaspersky.fr
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://www.update.microsoft.com/...
O16 - DPF: {6E32070A-766D-4EE6-879C-DC1FA91D2FC3} (MUWebControl Class) - http://www.update.microsoft.com/...
O16 - DPF: {E856B973-45FD-4559-8F82-EAB539144667} (Dell PC Checkup Installer Control) - http://pccheckup.dellfix.com/rel/41/install/gtdownde.cab
O20 - Winlogon Notify: WgaLogon - C:\WINDOWS\SYSTEM32\WgaLogon.dll
O21 - SSODL: WPDShServiceObj - {AAA288BA-9A4C-45B0-95D7-94D524869DB5} - C:\WINDOWS\system32\WPDShServiceObj.dll
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: avast! Antivirus - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - Unknown owner - C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe" /service (file missing)
O23 - Service: avast! Web Scanner - Unknown owner - C:\Program Files\Alwil Software\Avast4\ashWebSv.exe" /service (file missing)
O23 - Service: C-DillaSrv - C-Dilla Ltd - C:\WINDOWS\system32\DRIVERS\CDANTSRV.EXE
O23 - Service: Intel(R) PROSet/Wireless Event Log (EvtEng) - Intel Corporation - C:\Program Files\Intel\Wireless\Bin\EvtEng.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Fichiers communs\InstallShield\Driver\1150\Intel 32\IDriverT.exe
O23 - Service: NICCONFIGSVC - Dell Inc. - C:\Program Files\Dell\QuickSet\NICCONFIGSVC.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe
O23 - Service: Intel(R) PROSet/Wireless Registry Service (RegSrvc) - Intel Corporation - C:\Program Files\Intel\Wireless\Bin\RegSrvc.exe
O23 - Service: Intel(R) PROSet/Wireless Service (S24EventMonitor) - Intel Corporation - C:\Program Files\Intel\Wireless\Bin\S24EvMon.exe
O23 - Service: Intel(R) PROSet/Wireless SSO Service (WLANKEEPER) - Intel(R) Corporation - C:\Program Files\Intel\Wireless\Bin\WLKeeper.exe